These notes are a summary from Dr.Hornik's PPT Ch3


XML:

Extensible Markup Language
Markup?
Data being exchanged
Sent from computer-to-computer (intra and inter-organizationally)
Defining the data
Enclosing the data with descriptions of what the data is
<> Tags used to enclose data
Used to create Vocabularies
Standardized sets of tags (kind of like EDI)
XBRL is one such vocabulary

CONCEPTS:
Prolog:
the first line of any XML based document
<?xml version="1.0" encoding="UTF-8"?>
Element
A Tag set (the tag name, its attribute and data)
Root Element
Contains (or encloses) all the other elements
Parent Element:
» Contains other elements
» Used to represent information about one Instance of an entity
» For example a customer order
Child Element:
Enclosed by Parent element
Represents attributes describing the Parent Element
For example: customer name, date of order, items ordered, etc.
Attributes:
used to modify or clarify the data in an element
<elevation>130</elevation>
<elevation measureUnit = “meter”>130</elevation>
XML RULES:
The first line of an XML document must contain the prologue.
The main theme of the XML document – the root element - must enclose all the other elements in the document.
Every element must have an opening tag <> and a closing tag </>
Elements must be properly nested, that is you close the tag that was opened last – think of tags as using a LIFO convention or more properly a LOFC Last Opened First Closed convention (though it doesn’t have quite the same ring to it).
Elements can have attributes.
Attribute values are enclosed with “ ” and can have no spaces.


Author: Bechir Neili. The above notes are a summary to Dr Hornik's PPT presentation on XML: Ch3.